They've never had a reported incident of that happening. At least not yet. I suppose it could happen. The one with the nipple might be a little more likely for that to happen with, but again, hasn't happened yet.They do work awesome, had one on my 10-wheeler that had the drain plug on the side of the pan.I'm not too crazy about putting it on a vehicle that has the drain plug on the bottom of the pan, always wondered if someone was to run over something on the road, would it snap that off? (if the drain plug is facing towards the ground).